Americans for Prosperity is again citing an unscientific survey on health premiums to attack Democratic supporters of Obamacare – this time claiming in a new TV ad that premiums are up “by nearly 40 percent” in Michigan.

Ads criticizing the Affordable Care Act make the general claim that it’s “hurting” families. Some families could pay more for insurance, but millions of the uninsured will gain coverage. And millions will get subsidies to help pay for coverage.

Several ads make the misleading claim that premiums and health care costs are “skyrocketing” under the Affordable Care Act. Overall, both are growing at historically low rates. Some who buy their own insurance will pay more, but others will pay less.

Anti-Obamacare ads have claimed that “millions” lost their health insurance and their doctors because of the law. But policyholders weren’t denied coverage, and there’s evidence that far more gained insurance than had their plans canceled.

In a classic case of misdirection, the Senate Majority PAC claims the “out-of-state billionaire Koch brothers” are spending millions to elect Republican Bill Cassidy so that he will “fight for them” on issues such as their “fight to let flood insurance premiums soar.”

Senate Majority Leader Harry Reid wrongly blamed the conservative group Americans for Prosperity for promoting a “false” story of a woman whose insurance premiums went up $700 per month. AFP didn’t feature that woman’s story in any of its ads.

A TV ad from the conservative Americans for Prosperity recycles an old — and inaccurate — clip of Florida Rep. Steve Southerland blaming the Affordable Care Act for a “$1,200 increase” in health care premiums.